Method and apparatus for planarizing a polymer layer

ABSTRACT

A method for planarizing a polymer layer is provided which includes providing a substrate having the polymer layer formed thereon, providing a structure having a substantially flat surface, pressing the flat surface of the structure to a top surface of the polymer layer such that the top surface of the polymer layer substantially conforms to the flat surface of the structure, and separating the flat surface of the structure from the top surface of the polymer material layer.

BACKGROUND

The present disclosure relates generally to semiconductor manufacturingand, more particularly, to a method and apparatus for planarizing apolymer layer in semiconductor manufacturing.

Various polymer coatings are frequently used in semiconductormanufacturing. For example, one such polymer coating is a photoresist orresist layer. Another polymer coating is an antireflection coating (ARC)layer. Still another polymer coating is a planarizing layer of amultiple-resist system. These polymer coatings are typically formed on awafer substrate by dissolving the polymer in a solvent carrier andapplying it to the wafer substrate in liquid form by spin-coating. Inspin-coating, the wafer substrate is typically spun at very high speedsbetween hundreds and thousands of rotations-per-minute (rpm) to achievea predetermined thickness. The polymer coating is then baked toevaporate out the solvent. Accordingly, the polymer coating is uniformlycoated on the wafer substrate if there is an even topography on thesubstrate. That is, the polymer coating has a flat and/or uniformsurface if the surface of the wafer substrate is flat and/or uniform.However, in many situations, the topography of the underlying wafersubstrate is not flat and/or uniform. In these situations, spin-coatingmay result in non-flat and/or non-uniform polymer surface.

One method for flattening and/or planarizing the polymer surface is bychemical-mechanical polish (CMP) which uses a combination of mechanicalpolishing and chemical reaction. Although CMP is a well-developedtechnique for flattening and/or planarizing harder material films suchas SiO₂ and Cu, it has not been adequately developed for fatteningand/or planarizing polymer coatings. Even if CMP is successfullydeveloped for polymer coatings in the future, the CMP process isexpensive and time consuming. Furthermore, CMP also consumes expensivepolishing compounds. Another method for flattening and/or planarizing apolymer layer such as a photoresist layer is by using a double coatingof a photoresist and performing a photoresist etch back process toplanarize the photoresist layer. However, this method is time consumingand costly due to the additional photoresist coating and extra etch backprocess.

It is well known that the topography of the wafer substrate will impactthe lithography process margin, for example depth of focus (DOF).Accordingly, various patterned structures such as gate electrodes, metalline, and passive elements on the substrate, when processed in the frontend or backend, need to have a material layer, such as a dielectricfilm, formed thereon, and the material layer may undergo CMP and/or anetch back process to achieve a quasi-planar surface. However, due topattern density effects and different layout designs, a substantiallyequivalent planar surface on the wafer cannot be easily achieved withcurrent planarizing techniques, particularly between the isolated areasand pattern dense areas. Furthermore, a polymer material, such as aphotoresist, overlying the wafer will also conformably include theuneven surface, and may result in degradation of the lithography processmargin.

Therefore, a need exists for a simple and cost-effective method forplanarizing a polymer layer overlying a non-uniform surface.

BRIEF DESCRIPTION OF THE DRAWINGS

Aspects of the present disclosure are best understood from the followingdetailed description when read with the accompanying figures. It isemphasized that, in accordance with the standard practice in theindustry, various features are not drawn to scale. In fact, thedimensions of the various features may be arbitrarily increased orreduced for clarity of discussion.

FIG. 1 is a flowchart of a method for planarizing a polymer layeraccording to various aspects of the present disclosure;

FIGS. 2A-2D are cross-section views of the polymer layer at variousstages of manufacturing in accordance with the method of FIG. 1;

FIG. 3 is a diagrammatic view of an apparatus for planarizing a polymerlayer according to various aspects of the present disclosure;

FIG. 4 is a diagrammatic view of an alternative apparatus forplanarizing a polymer layer according to various aspects of the presentdisclosure; and

FIG. 5 is a diagrammatic view of another alternative apparatus forplanarizing a polymer layer according to various aspects of the presentdisclosure.

DETAILED DESCRIPTION

The present disclosure relates generally to semiconductor manufacturingand more particularly, to a method and apparatus for planarizing apolymer layer overlying a non-uniform surface. It is understood,however, that specific embodiments are provided as examples to teach thebroader inventive concept, and one of ordinary skill in the art caneasily apply the teaching of the present disclosure to other methods ordevices. In addition, it is understood that the methods and apparatusdiscussed in the present disclosure include some conventional structuresand/or processes. Since these structures and processes are well known inthe art, they will only be discussed in a general level of detail.

Furthermore, reference numbers are repeated throughout the drawings forsake of convenience and example, and such repetition does not indicateany required combination of features or steps throughout the drawings.Moreover, the formation of a first feature over, on, adjacent, abutting,or coupled to a second feature in the description that follows mayinclude embodiments in which the first and second features are formed indirect contact, and may also include embodiments in which additionalfeatures may be formed interposing the first and second features, suchthat the first and second features may not be in direct contact. Also,the formation of a feature on a substrate, including for example,etching a substrate, may include embodiments where features are formedabove the surface of the substrate, directly on the surface of thesubstrate, and/or extending below the surface of the substrate (such as,trenches).

Referring to FIG. 1, illustrated is a flow chart for a method 100 forplanarizing a polymer layer formed on a substrate. Also referring toFIGS. 2A to 2D, illustrated are cross-section views of the polymer layerat various stages of manufacturing in accordance with the method 100 ofFIG. 1. In FIGS. 1 and 2A, the method 100 begins with block 102 in whicha substrate 202, such as a semiconductor wafer, is provided. Thesubstrate 202 may include silicon in a crystalline structure. Inalternative embodiments, the substrate 202 may optionally include otherelementary semiconductors such as germanium, or may include a compoundsemiconductor such as, silicon carbide, gallium arsenide, indiumarsenide, or indium phosphide. Additionally, the substrate 202 mayinclude a silicon on insulator (SOI) substrate, polymer-on-siliconsubstrate, or “silicon-on-nothing” (“SON”) substrate including a thininsulation layer. The thin insulation layer includes air and/or othergaseous composition. The substrate 202 may further comprise one or morelayers formed on the substrate. Examples of layers that may be formedinclude doped layers, insulative layers, epitaxial layers, conductivelayers including polysilicon layers, dielectric layers, and/or othersuitable semiconductor layers. The substrate 202 may be supported by asubstrate support 204.

The substrate 202 is illustrated with various features 206 formed on thesubstrate. The features 206 may include conductive features, insulativefeatures, or other features associated with semiconductor devices. Apolymer material layer 208 may be formed over the features 206 andsubstrate 202. The polymer layer 208 may include a photoresist layer, anantireflection coating (ARC) layer, a planarizing layer of amultiple-resist system, or other suitable polymer coating. For example,the polymer layer 208 may be formed over the substrate 202 by aspin-coating process. The polymer layer 208 is formed by dissolving apolymer in a solvent carrier and applying it to the substrate 202 inliquid form by spin-coating. In spin-coating, the substrate 202 is spunat very high speeds to achieve a predetermined thickness for the polymerlayer 208. The polymer layer 208 is then baked to evaporate out thesolvent. However, a top surface 210 of the polymer layer 208 may not besubstantially flat and/or uniform because of the non-uniformity of theunderlying surface including the features 206 and/or substrate 202.

The method 100 continues with block 104 in which a structure 220 havinga substantially flat and smooth surface 222 is provided. The surface 222of the structure 220 has an area that substantially covers the entiresurface area of the substrate 202. The structure 220 may be formed ofquartz, glass, metal, or other suitable hard material whose surface cansupport nanometer-scale smoothness. Additionally, the material of thestructure 220 may be selected to include a hardness that issubstantially higher than the polymer layer 208. The surface 222 may betreated with a non-adhesive or non-sticking material such that there isvery low, or substantially no adhesion to the polymer surface whencontacting with the polymer layer 208. Alternatively, the surface 222 ofthe structure 220 may optionally be coated with a film of Teflon orTeflon-like material, such as polytetrafluoroethylene (PTFE),perfluoroalkoxy (PFA), and fluorinated ethylene propylene (PFA), orcombinations thereof, that functions as a non-adhesive surface.

The method 100 continues with block 106 in which the polymer layer 208may be softened by heating the polymer layer with a heat source. In oneembodiment, the polymer layer 208 may be softened by heating the polymerlayer via the structure 220. For example, the heat source may beintegrated within the structure 220 as will discussed later.Alternatively, in another embodiment, the polymer layer 208 may besoftened by heating the substrate 202 via the substrate support 204.Further, in yet another embodiment, the polymer layer 208 may besoftened via heating from a combination of the structure 220 and thesubstrate support 204. The heating temperature for the polymer layer 208may be selected as a function of a pressure applied to the structure 220when contacting with the polymer layer 208 for optimumflatness-separation-throughput characteristics. For example, a highertemperature softens the polymer layer 208 more, and thus the flatteningpressure applied to the structure 220 may be less. However, if thetemperature is too high, the polymer layer 208 may tend to stick to theflat surface 222 of the structure 220. Additionally, the heatingtemperature may also be a function of the type of material of thepolymer layer 208. For example, the polymer layer 208 may be heated to aglass transition temperature of the polymer material of the polymerlayer or to a temperature range within the glass transition temperaturesuch as within 90% of the glass transition temperature.

In FIG. 2B, the method 100 continues with block 108 in which the flatsurface 222 of the structure 220 may be pressed 230 to the top surface210 of the polymer layer 208. The contacting of the flat surface 222 ofthe structure 220 and the top surface 210 of the polymer layer 208 ispreferably performed in a vacuum environment to eliminate thepossibility of trapping air and/or air bubbles between the structure 220and the polymer layer 208. A precisely controlled pressure 230 may beapplied to the structure 220 such that the top surface 232 of thepolymer layer 208 substantially conforms to the flat surface 222 of thestructure 220. Further, the various features 206 formed on the substrate202 are not damaged or altered during the pressing action.

It should be noted that the heating of the polymer layer 208 asdiscussed above in block 106 may be performed immediately after the flatsurface 222 of the structure 220 contacts the polymer layer 208 suchthat the polymer layer 208 softens and conforms to the flat surface 222during the pressing and flattening action. Alternatively, the heating ofthe polymer layer 208 may optionally be performed before the structure222 contacts the polymer layer 208, or may be performed simultaneouslywith the contact.

In FIG. 2C, the method 100 continues with block 110 in which the flatsurface 222 of the structure 220 may be separated 240 from the topsurface 232 of the polymer layer 206. Accordingly, the polymer layer 208remains substantially flat and uniform after the flat surface 222 of thestructure 220 is removed from contacting the top surface 232 of thepolymer layer 208. Further, the non-adhesive flat surface 222 of thestructure 220 aids in preventing sticking of the top surface 232 of thepolymer layer 208 during the separation.

In FIG. 2D, the method 100 continues with block 112 in which the polymerlayer 208 may be cooled to a desired temperature. Accordingly, thesubstrate 202 may be transferred to a substrate-cooling support 250 thatprovides for cooling the substrate 202 and polymer layer 208. Thepolymer layer 208 having a substantially flat and uniform surface 232 isnow available for further semiconductor processing. In one embodiment,the polymer layer 208 may be configured as a photoresist layer, and thusthe method 100 provides a substantially flat and uniform photoresistlayer which is optimal for patterning in a photolithography process orother suitable semiconductor process. In another embodiment, the polymerlayer 208 may be configured as an antireflection coating (ARC) layer,and thus the method 100 provides a substantially flat and uniform ARClayer which is optimal for forming other semiconductor material layers(e.g., photoresist) thereon. In yet another embodiment, the polymerlayer 208 may be configured as a planarizing layer of a multiple-resistsystem, and thus the method 100 provides a substantially flat anduniform planarizing layer which is optimal for a photolithographyprocess or other suitable semiconductor process.

Referring to FIG. 3, illustrated is diagrammatic view of an apparatus300 for planarizing a polymer layer according to various aspects of thepresent disclosure. The apparatus 300 may be utilized for performing themethod 100 of FIG. 1, and the polymer layer may be similar to thepolymer layer 208 discussed in FIGS. 2A to 2D. Accordingly, similarfeatures in FIGS. 2 and 3 are numbered the same for clarity. Theapparatus 300 includes a chamber 302 capable of providing a vacuumenvironment 304 therein. The apparatus 300 further includes a substratetable 306 and a pinned-substrate support 308 for supporting a substrate202. The pinned-substrate support 308 may reduce the possibility ofdamaging and/or distorting the substrate 202 by foreign particles beingtrapped between the substrate and the substrate table 306. The apparatus300 further includes a substrate-cooling table 310 adapted andconfigured to cool the substrate 202 (including the polymer layer 208)to a desired temperature.

The apparatus 300 further includes a flattening structure 312 having asubstantially flat and non-adhesive surface 314 similar to the onediscussed in FIG. 2. The flattening structure 312 may be formed ofquartz, glass, metal, or other suitable hard material whose surface cansupport nanometer-scale smoothness. Additionally, the material of theflattening structure 312 may be selected to include a hardness that issubstantially higher than the polymer layer 208. The surface 314 may betreated with a non-adhesive or non-sticking material such that there isvery low, or substantially no adhesion to the polymer surface whencontacting with the polymer layer 208. Alternatively, the surface 314 ofthe flattening structure 312 may optionally be coated with a film ofTeflon or Teflon-like material, such as polytetrafluoroethylene (PTFE),perfluoroalkoxy (PFA), and fluorinated ethylene propylene (PFA), orcombinations thereof, which functions as a non-adhesive surface.

Additionally, the flattening structure 312 further includes a heater 315for heating the polymer layer 208 to a predetermined temperature. In oneembodiment, the temperature range is between about 50 to about 120degree C. In another embodiment, the temperature range is between about120 to about 250 degree C. In still another embodiment, the temperatureis within a temperature range of a glass transition temperature of thepolymer layer 208. The heating temperature for the polymer layer 208 maybe selected as a function of a pressure applied to the flatteningstructure 312 when contacting with the polymer layer 208 for optimumflatness-separation-throughput characteristics. The heater 315 ispreferably a flash annealing lamp that is configured to be quicklyturned on after the polymer layer 208 is pressed against the flatteningstructure 312, and to be quickly turned off after the polymer layer 208is softened and flattened. Alternatively, the heater 315 may optionallyinclude heating coils or other suitable heat sources known in the art.

The flattening structure 312 includes a spherical support 320 that isadapted and configured to support a pressing arm 322. The pressing arm322 includes a ball interface 324 that pivotally moves within thespherical support 320 of the fattening structure 312. Accordingly, theflattening structure 312 is allowed to move freely in various directions326, 328 to eliminate wedging between the flat surface 314 of theflattening structure 312 and the surface of the polymer layer 208.Otherwise, the polymer layer 208 thickness may be tilted from one end tothe other. A precisely controlled and adjustable pressure may be appliedto the pressing arm 322 to press the flattening structure 312 to thepolymer layer 208 and substrate 202. The amount of pressure may dependon the softness of the polymer layer 208. Further, the vacuumenvironment 304 aids in preventing air bubbles from being trappedbetween the flattening structure 312 and the polymer layer 208 duringthe contact.

It is understood that the pressing action of the apparatus 300 may beperformed with the substrate table 306 in a stationary position whilethe flattening structure 312 is moved to and from the substrate table306 via the pressing arm 322. Alternatively, the pressing action of theapparatus 300 may optionally be performed with the pressing arm 322 in astationary position while the substrate table 306 is moved to and fromthe flattening structure 312. Furthermore, the pressing action of theapparatus 300 may alternatively be performed by a combinational movementof the pressing arm 322 and the substrate table 306.

Referring to FIG. 4, illustrated is a diagrammatic view of analternative apparatus 400 for planarizing a polymer layer according tovarious aspects of the present disclosure. The apparatus 400 of FIG. 4is similar to the apparatus 300 of FIG. 3 except for a flatteningstructure 402 that includes a contacting surface 404 that is configuredto be thin and flexible. For example, the contacting surface 404 mayinclude a thin aluminum layer whose hardness and thickness are optimizedto conform to macro surface irregularities while sufficiently stiff inorder to flatten the polymer layer 208 during processing. The pressingpressure may be provided with a liquid element 406 inside the flatteningstructure 402. Additionally, the liquid 406 may be heated to soften thepolymer layer 208 when the surface 404 directly contacts the top surfaceof the polymer layer 208.

Aluminum is preferably selected since aluminum is easy to machine andpolish as well as its compatibility with Teflon or Teflon-like materials(for non-adhesive surface). However, it is understood that otherthermally conductive materials with good tensile strength may be usedinstead of aluminum. In the present embodiment, quick heating andremoval of the flattening structure is less important. Accordingly, theflattening structure 402 may be maintained at a constant temperature asthe top surface of the polymer layer 208 flattens and conforms to thecontacting surface 404 of the flattening structure 402 during thepressing action.

Referring to FIG. 5, illustrated is a diagrammatic view of anotheralternative apparatus 500 for planarizing a polymer layer according tovarious aspects of the present disclosure. The apparatus 500 of FIG. 5is similar to the apparatus 300 of FIG. 3 except for a compressiblesupport 502 instead of the pinned-substrate support 308. Thecompressible support 502 may be configured as a balloon-type structurethat is positioned between the substrate 202 and the substrate table306. Accordingly, even if the substrate 202 has a non-uniform thicknessand/or has some micro-bending, the flexibility of the compressiblesupport 502 allows the substrate 202 and polymer layer 208 tosubstantially conform to the flat surface 314 of the flatteningstructure 312 during the pressing action.

Thus, a method for planarizing a polymer layer is provided whichincludes providing a substrate having the polymer layer formed thereon,providing a structure having a substantially flat surface, pressing theflat surface of the structure to a top surface of the polymer layer suchthat the top surface of the polymer layer substantially conforms to theflat surface of the structure, and separating the flat surface of thestructure from the top surface of the polymer layer. In someembodiments, the step of pressing the flat surface of the structure isperformed in a vacuum environment to prevent air from being trappedbetween the flat surface of the structure and the top surface of thepolymer layer.

In other embodiments, the method further includes softening the polymerlayer prior to pressing the flat surface of the structure. In some otherembodiments, the step of softening the polymer layer includes heatingthe polymer layer to a temperature from about 50 to about 250 degree C.In other embodiments, the step of softening the polymer layer includesheating the polymer layer to a temperature range within a glasstransition temperature of the polymer layer. In some other embodiments,the method further includes comprising cooling the polymer layer afterseparating the flat surface of the structure. In other embodiments, thestructure further includes a non-adhesive surface. In still otherembodiments, the polymer layer is of a type selected from the groupconsisting of: a photoresist layer, an antireflection coating (ARC)layer, and a planarizing layer.

Also provided is an apparatus for planarizing a polymer layer whichincludes a flattening structure having a substantially flat surface, anda pressing mechanism operatively coupled to the flattening structure andconfigured to press the flat surface of the flattening structure to atop surface of the polymer layer such that the top surface of thepolymer layer substantially conforms to the flat surface of theflattening structure. In some embodiments, the apparatus furtherincludes a chamber capable of providing a vacuum environment therein, atable located within the chamber and configured to support a substratehaving the polymer layer formed thereon. In some other embodiments, theapparatus further includes a heat source for softening the polymer layeron the substrate. In other embodiments, the heat source is integratedwith the flattening structure and configured to heat the polymer layerto a temperature from about 50 to about 250 degree C.

In still other embodiments, the flattening structure includes a materialselected from the group consisting of: a quartz material, a glassmaterial, a metal material, and combinations thereof. In some otherembodiments, the flattening structure includes a material having ahardness that is substantially higher than the polymer layer. In otherembodiments, the apparatus further includes a cooling mechanism forcooling the substrate. In some other embodiments, the pressing mechanismincludes a spherical support and the flattening structure includes apivot structure for pivoting with the spherical support. In otherembodiments, the flat surface of the flattening structure includes anon-adhesive surface. In still other embodiments, the non-adhesivesurface is of the type selected from the group: apolytetrafluoroethylene (PTFE), a perfluoroalkoxy (PFA), and afluorinated ethylene propylene (PFA), and combinations thereof.

Additionally, a method for planaring a material layer formed over asubstrate is provided. The method includes providing a flattening blockhaving a substantially flat and non-adhesive surface, heating theflattening block such that the flat and non-adhesive surface of theflattening block is at a predetermined temperature, contacting thesurface of the flattening block to the top surface of the material layerand applying a pressure to the flattening block such that the topsurface of the material layer becomes planarized, and separating theflattening block from the top surface of the material layer. In someembodiments, the material layer is selected from the group consistingof: a photoresist layer, an antireflection coating (ARC) layer, and aplanarizing layer. In some other embodiments, the method furtherincludes performing the method in a vacuum environment.

Although only a few exemplary embodiments of this invention have beendescribed in detail above, those skilled in the art will readilyappreciate that many modifications are possible in the exemplaryembodiments without materially departing from the novel teachings andadvantages of this invention. It is understood that various differentcombinations of the above-listed steps can be used in various sequencesor in parallel, and there is no particular step that is critical orrequired. Also, features illustrated and discussed above with respect tosome embodiments can be combined with features illustrated and discussedabove with respect to other embodiments. Accordingly, all suchmodifications are intended to be included within the scope of thisinvention.

Several different advantages exist from these and other embodiments. Themethod and apparatus disclosed herein provide a simple andcost-effective technique for planarizing a polymer layer overlying anon-uniform surface. The various embodiments disclosed herein use asoften-and-press (SAP) technique to planarize the surface of the polymerlayer. Additionally, there is substantially no material consumption andthere is less probability that defects are introduced to the surface ofthe polymer layer as compared to chemical-mechanical polishing (CMP)techniques. Furthermore, unlike CMP which is film sensitive, the SAPtechnique is universally applicable to most polymer materials.

What is claimed is:
 1. A method for planarizing a polymer layer,comprising: providing a substrate having the polymer layer formedthereon; providing a structure having a flexible contact layer with asurface, the surface being substantially flat when the contact layer isin a non-flexed state and providing a nanometer-scale smoothness,wherein the structure includes a non-vacuumed chamber containing aliquid, wherein the liquid is within the non-vacuumed chamber prior toany engagement of the structure with the substrate having the polymerlayer formed thereon, and wherein the structure is attached to apressing arm by a pivotal interface allowing the flexible contact layerto pivot with respect to the substrate; softening the polymer layer,wherein softening the polymer layer includes heating the liquid withinthe non-vacuumed chamber to facilitate softening of the polymer layer,wherein the heating the liquid occurs prior to any engagement of thestructure with the substrate having the polymer layer formed thereon;pressing the surface of the contact layer to a top surface of thesoftened polymer layer such that the top surface of the polymer layer issubstantially flattened by the surface of the contact layer, wherein,during the pressing, the pressing arm exerts pressure on the substratevia the pivotal interface, wherein the contact layer flexes during thepressing, wherein the structure prevents the liquid from physicallycontacting the substrate having the polymer layer formed thereon whenthe liquid is within the non-vacuumed chamber of the structure and thesurface of the contact layer is pressed to the top surface of thesoftened polymer layer, the liquid not generating the pressure to pressthe surface of the contact layer to the top surface of the softenedpolymer layer, and wherein the pressure to press the surface of thecontact layer to the top surface is provided via the structure havingthe contact layer; separating the flat surface of the contact layer fromthe top surface of the softened polymer layer, wherein the liquidremains in the non-vacuumed chamber of the structure after separatingthe flat surface of the contact layer from the top surface of thesoftened polymer layer; and cooling the polymer layer after theseparating of the flat surface of the contact layer.
 2. The method ofclaim 1, wherein the pressing the surface of the contact layer isperformed in a vacuum environment to prevent air from being trappedbetween the surface of the contact layer and the top surface of thepolymer layer.
 3. The method of claim 1, wherein the softening thepolymer layer includes heating the polymer layer to a temperature fromabout 50 to about 250 degree C.
 4. The method of claim 1, wherein thesoftening the polymer layer includes heating the polymer layer to atemperature range, wherein a glass transition temperature of the polymerlayer is within the temperature range.
 5. The method of claim 1, whereinthe surface is a non-adhesive surface.
 6. The method of claim 1, whereinthe polymer layer is of a type selected from the group consisting of: aphotoresist layer, an antireflection coating (ARC) layer, and aplanarizing layer.
 7. A method for planarizing a material layer formedover a substrate, the method comprising: supporting the substrate on atable with a compressible support; providing a flattening block having aflexible contact layer that has a substantially flat and non-adhesivecoated surface, the coated surface including a film comprising at leastone of polytetrafluoroethylene (PTFE), perfluoroalkoxy (PFA), orfluorinated ethylene propylene (FEP), wherein the flattening blockfurther includes a non-vacuumed chamber containing a liquid, wherein theliquid is within the non-vacuumed chamber prior to any engagement of theflattening block with the material layer, and wherein the flatteningblock is secured to a pressing arm by a pivotal interface such that theflexible contact layer pivots with respect to the supported substrate;softening the material layer, wherein softening the material layerincludes heating the liquid within the non-vacuumed chamber tofacilitate softening of the material layer, wherein the heating occursprior to any engagement of the flattening block with the material layer;contacting the flat and non-adhesive coated surface of the contact layerto a top surface of the material layer and applying a pressure by thepressing arm through the pivotal interface and through the flatteningblock to the top surface of the material such that the top surface ofthe material layer becomes planarized, wherein the compressible supportis compressed and the contact layer flexes during the application of thepressure, wherein the flattening block prevents the liquid fromphysically contacting the material when the liquid is within thenon-vacuumed chamber of the flattening block and the flat andnon-adhesive coated surface of the contact layer contacts the topsurface of the material layer, wherein the liquid not generating thepressure to press the surface of the contact layer to the top surface ofthe softened polymer layer; separating the contact layer of theflattening block from the top surface of the material layer, wherein theliquid remains in the non-vacuumed chamber of the flattening block afterseparating the contact layer of the flattening block from the topsurface of the material layer; and cooling the material layer after theseparating of the contact layer.
 8. The method of claim 7, wherein thematerial layer is selected from the group consisting of: a photoresistlayer, an antireflection coating (ARC) layer, and a planarizing layer.9. The method of claim 7, further comprising performing the method in avacuum environment.
 10. A method for planarizing a material layer formedover a substrate, the method comprising: providing a flattening blockhaving a flexible contact layer that has a substantially flat andnon-adhesive surface, wherein the flattening block further includes anon-vacuumed chamber containing a liquid, wherein the liquid is withinthe non-vacuumed chamber prior to any engagement of the flattening blockwith the material layer; supporting the substrate on a table with acompressible support; heating the material layer to a temperature,wherein heating the material layer includes heating the liquid withinthe non-vacuumed chamber to facilitate heating of the material layer,wherein the heating occurs prior to any engagement of the flatteningblock with the material layer; bringing the flat and non-adhesivesurface of the contact layer to a top surface of the material layerusing a pivotal support attached to the flattening block that allows theflat and non-adhesive surface to pivot with respect to the top surface;pressing the flat and non-adhesive surface of the contact layer to thetop surface of the material layer such that the top surface of thematerial layer substantially conforms to the flat surface of the contactlayer, wherein the compressible support is compressed and the contactlayer flexes during the pressing, wherein the flattening block preventsthe liquid from physically contacting the material layer when the liquidis within the non-vacuumed chamber of the flattening block and the flatand non-adhesive surface of the contact layer is pressed to the topsurface of the material layer, the liquid not generating the pressure topress the flat and non-adhesive surface of the contact layer to the topsurface of the material layer, and wherein the pressure to press theflat non-adhesive surface of the contact layer to the top surface of thematerial layer is provided via the pivotal support; separating thecontact layer of the flattening block from the top surface of thematerial layer, wherein the liquid remains in the non-vacuumed chamberof the flattening block after separating the contact layer of theflattening block from the top surface of the material layer; and coolingthe material layer after the separating of the contact layer.
 11. Themethod of claim 10, wherein the pressing includes one of: maintainingthe substrate stationary and moving the flattening block to contact thetop surface of the material layer; and maintaining the flattening blockstationary and moving the substrate to contact the top surface of thematerial layer to the flattening block.
 12. The method of claim 10,wherein the temperature of the heating is predetermined in considerationof a pressure that is to be applied to the flattening block during thepressing.
 13. The method of claim 10, wherein the contacting isperformed in a vacuum environment to prevent air from being trappedbetween the flat surface of the flattening block and the top surface ofthe material layer.
 14. The method of claim 10, wherein the flatteningblock is formed of a material having a hardness substantially higherthan that of the material layer.
 15. The method of claim 14, wherein thematerial of the flattening block is of a type selected from the groupconsisting of: a quartz material, a glass material, a metal material,and combinations thereof.
 16. The method of claim 10, wherein thematerial layer is selected from the group consisting of: a photoresistlayer, an antireflection coating (ARC) layer, and a planarizing layer.17. The method of claim 10, wherein the non-adhesive surface includes aperfluoroalkoxy (PFA) material.
 18. The method of claim 1, furthercomprising configuring the thickness and rigidity of the contact layersuch that the surface of the contact layer can conform to macro-surfaceirregularities of the polymer layer during the pressing.
 19. The methodof claim 1 wherein the flexible contact layer includes at least one fromthe group consisting of quartz, glass, and metal.
 20. The method ofclaim 10, wherein the pressing includes moving the flattening block tocontact the top surface of the material layer and moving the substrateto contact the top surface of the material layer to the flatteningblock.
 21. The method of claim 10, wherein the non-adhesive surfaceincludes a fluorinated ethylene propylene (FEP) material.
 22. The methodof claim 7, wherein the flattening block includes at least one of aquartz material, a glass material, or a metal material.
 23. The methodof claim 7, wherein the heating of the liquid is configured to heat thematerial layer to a temperature between about 50° C. and about 250° C.